This project aims to bridge a gap between basic research on neurophysiology of vision and clinical research on visual disorders. We propose to construct two microcomputer-based visual stimulator/data analyzers specially designed for use as diagnostic instruments. The basic method is to record from the scalp the evoked potentials produced by patterned stimuli. This is one of the simplest methods available to study human vision. But by using a sophisticated approach this simple method can provide a powerful tool. The instruments will utilize versatile up-to-date electro-optical displays of our own design for visual stimulation. The instruments will display a variety of two-dimensional spatio-temporal patterns. For the data reduction a novel, more efficient version of Wiener analysis for both linear and nonlinear systems recently developed in our laboratory will be used. The methods of stimulation and of data analysis have been thoroughly tested in extensive basic research in lower animals (some with visual deficits) and in pilot experiments on humans. By bringing versatile and well controlled visual stimulators and rigorous and powerful analytic methods into the clinical laboratory we hope to advance our understanding of normal human vision and of pathologies of the visual pathway from eye to cortex.